Branch : Computer Science and Engineering
Subject : Wireless Communication
Combined Path Loss and Shadowing
Introduction:
Models for path loss and shadowing can be superimposed to capture power falloff versus distance along with the random attenuation about this path loss from shadowing.
Combined Path Loss:
- In this combined model, average dB path loss (μψ dB) is characterized by the path loss model and shadow fading, with a mean of 0 dB, creates variations about this path loss
- Specifically, this curve plots the combination of the simplified path loss model and the log-normal shadowing random process
- For this combined model the ratio of received to transmit power in dB is given by:
ψdB is a Gauss-distributed random variable with mean zero and variance σ2ψdB.
- The path loss decreases linearly relative to log10 d with a slope of 10γ dB/decade, where γ is the path loss exponent.
- The variations due to shadowing change more rapidly, on the order of the decorrelation distance Xc